Cold, flu or flu-like infection – which is which?

A runny nose and a scratchy throat is termed a cold. The name stems from the fact that we often have the impression that this complaint is caused by cold air, a draft or hypothermia. In fact it is our immune system that is either strong enough to stop the pathogens from becoming active or to fight them off if there is a flu-like infection. We then notice this due to the cold symptoms. Colds are usually caused by viruses (mainly rhinoviruses). The risk of infection is very high and only a healthy immune system can protect us.

Many viruses trigger a strong feeling of illness - not only bona fide flu viruses. However, we only use the term real flu when the trigger of the symptoms is influenza virus. If other viruses trigger the cold symptoms, experts call this a flu-like infection.

What happens in the body when you have a cold?

Colds are usually caused by droplet infections. The pathogens spread by means of small droplets, for example when a sick person sneezes in a radius of around 3 metres, and get into our body when we breathe. Infections from contaminated objects, i.e., objects contaminated with pathogens (smear infections) such as door handles, towels, keyboards or toys are also possible. We catch a cold if our immune system fails to fight off the viruses before they trigger the symptoms of disease. The immune system must then remain active. Its defence reaction triggers the symptoms. The immune cells are mainly found on mucous membranes. Therefore there is a scratchy throat and swelling of the nasal mucous membranes (a cold or rhinitis). If the pathogens travel further, the infection can spread to the bronchial mucous membranes and result in bronchitis with a cough.

What are viruses? How do they differ from bacteria?

Bacteria are small life forms in their own right. They are composed of one single cell (unicellular organism). If we count the cells in our body, only 10 % of them are human cells and the remaining 90 % are bacteria! These bacteria taken together weigh around 2 kg and include an estimated 10,000 different types. Some of them are vital for us because they support digestion and the immune system for example, while others colonise the skin and mucous membranes without being noticed and are only a problem if they have the chance to multiply unchecked. This happens for example during a cold if the mucous membranes are already damaged due to dry air and defence against viruses. Then it is easy for the disease-causing bacteria to get "on top" and to trigger a bacterial superinfection in addition to the viral infection. There are also bacteria that are dangerous pathogens with a high risk of infection, even in small numbers.

In contrast to bacteria, viruses are not a self-contained life form. They are much smaller – only around one hundredth of the size of bacteria. They need so-called host cells to be able to multiply. When viruses infect a cell of the body, they then reprogramme this host cell so that the cell produces more viruses and, thus, ensures multiplication and spreading.

Precisely because viruses are not a self-contained life form, they cannot be countered with antibiotics (anti = against, bios = life) – in contrast to bacteria.

Does a flu jab really help?

Yes and no! A flu jab can provide protection against those pathogens in the vaccination. The Robert Koch Institute (RKI) says that the protection after vaccination depends on the state of your health, your age and how closely the vaccine matches the flu viruses in circulation. This means: It does not protect everyone to the same extent. There are so-called "vaccination failures". These are often people with weakened immune systems who have an insufficient immune response to the vaccination. The flu jab does not protect against other cold viruses as well, but only those flu viruses that are in the vaccine.

How long does flu or a cold last for?

As a general rule of thumb for flu-like infections, that is colds: It takes 3 days to show up, stays for 3 days and takes 3 days to go. The majority of infections are overcome after two weeks at the latest. Colds that last for longer indicate a weakened immune system. Real flu can last for longer – especially the weakness. Only children overcome an infection much more quickly. This is down to their often stronger powers of self-healing. This also includes fever. Adults usually have a temperature less often but also fight off the infection less effectively than children.

What can you do to prevent catching a cold?

The best protection against infections is a healthy immune system. This can be strengthened with a balanced diet with plenty of vitamins and minerals as well as regular exercise in the fresh air etc. Stimulation therapies for the immune system are also beneficial – e.g., sauna, water treading, dew cures, alternate foot baths or alternate showers (long: warm, short: cold). Lymph remedies can be taken to prevent colds as a strong immune system requires a strong lymph system.Make sure that there is high humidity in the rooms that you live in! Dry air from the heating in winter dries out mucous membranes. This provides viruses with a good breeding ground.

Which home remedies help colds?

Most importantly: Rest, warmth and drink plenty.

Inhalations with warm water vapour can help colds. Essential oils such as peppermint, eucalyptus and thyme can be added to the water for inhalation.

Onions are also a great home remedy: especially in the form of onion juice for coughs and onion packs for earache.

Gargling with sage tea can help to relieve the symptoms of a sore throat.

Leg compresses have proven to be good for fever.

Cooling or warming compresses and pads on the throat and chest can relieve Symptoms.

Good old chicken soup is considered to be an old home remedy for colds.

Note also: A large part of the immune system resides in the bowel. Therefore, support measures are important for a healthy bowel: Use pre- and probiotics.

Cold/flu during pregnancy – what can I do?

What is of utmost importance is: Self-medication during pregnancy is not recommended. Always consult your doctor, alternative practitioner or pharmacist on whether the home remedies that you wish to use are really suitable for pregnant women.For example, sweating cures with fever teas, but also proven herbs such as sage and thuja in the form of essential oils are unsuitable.On the other hand, there is a complete series of homoeopathic remedies that can also be used by pregnant women and which can provide relief from colds – for example Gripps® SL drops or tablets.